A little under a fortnight before the swimming starts in London, Rebecca Adlington is fit, healthy and focused on retaining the two gold medals she won in Beijing four years ago. But in the pursuit of history Adlington, more than anyone, realises she is without one advantage which helped her soar in China – the element of surprise.

Back in 2008 the effervescent 19‑year‑old from Mansfield was unknown to all but the truest of swimming aficionados, but after triumphing in the 800m and 400m freestyle – setting a world record time in the former and becoming the first British swimmer to win two Olympic gold medals since 1908 – Adlington became one of the most recognisable faces in Britain and, more significantly, one of the stars of her own sport.

She has maintained that status since, particularly after winning respective gold and silver medals in the 800m and 400m events at last year's world championships in Shanghai, and now goes into these Games as the principal target for her rivals.

"Everyone wants to beat me," Adlington said. "I don't [feel the pressure of that] because I want to beat everyone else and I've never been to a meet where the people who go in as the top three finish as the top three in every single race. It happens, it's life, and that's what is so exciting about sport in general.

"I am not under the illusion that I am going to win any race comfortably. It is going to be a fight, there are going to be other girls coming through who shock everyone. I know that because nobody expected me to do what I did in Beijing. It always happens; people always bring it out of the bag in Olympic year – that's what makes Olympic year so brilliant. I'm looking forward to seeing who that person is myself."

Having posted the fastest two times in the world this year, Adlington is the red-hot favourite for the 800m, but doing so in the 400m appears less certain, with Italy's Federica Pellegrini, the world champion and world record holder, undeniably the woman to beat over the shorter distance. Adlington is refusing to worry about losing one of her titles, however, insisting she will take whichever result comes her away with a level head having "done absolutely everything possible" to succeed during a gruelling training regime under the guidance of her long-serving coach, Bill Furniss.

The 23-year-old admits to having suffered extreme "mental tiredness" as a result of her preparations for the Olympics and as she retreats to a holding camp in Edinburgh on Wednesday to taper down ahead of the Games, she could be forgiven for contemplating life away from the rigours of top-level competition.

"Who knows," replied Adlington when asked if this could be her last Olympics. "After the Games I'm taking two or three months off and am doing a [charity] bike ride in Zambia in October. Before that I also have Keri-Anne Payne's hen-do and wedding. When I come back from the cycling I will start to think about whether I want to carry on or not. I will sit down with Bill and see where he's at. I don't know how I am going to feel. But as far as the bike ride is concerned, I am definitely looking forward to doing something new."

All that matters now, however, is London 2012 and the chance for Adlington to fire this country's imagination all over again. "I don't want to let the opportunity of a home Olympics to go by," she said. "As swimmers we train for 50 weeks a year for one moment and, in my case, it's over in eight minutes. Actually it's ridiculous when you say it like that.

"It can go right, it can go wrong, it can go average, you just never know. I don't want to come out crying, I don't want to be upset, but at the same time I know that I cannot control the other girls; if they are faster and better than me then fair play to them, they deserve it. I am just glad I will be able to look back say: 'I have no regrets.' Whatever the outcome, I'll be happy."